Document US 2010/0063779 discloses a shoe with an integrated sensor system. The sensor system collects performance data that are transferred for further use via a communication port. The shoe contains a force sensor arranged in the sole structure for measuring, in a plurality of areas, pressure (force) exerted by the wearer's foot on the sole structure, and an electronic module configured to gather data from the sensors. The module is configured for transmitting the data to an external device for further processing. In one of the embodiments disclosed in US 2010/0063779, the pressure sensor comprises four elongated pressure-sensing cells, each of which contains a first and a second electrode as well as a force-sensitive resistive material disposed between the electrodes to electrically connect the electrodes together. When pressure is applied to the force-sensitive material, its resistivity changes, and the resulting change in resistance is detected by the electronic module. Materials exhibiting volume-based resistance behavior are used as the force-sensitive material: when such material is compressed, conductive particles contained therein move closer together, whereby conductive paths are formed and the resistance decreases. If another resistance vs. pressure characteristic is needed, a suitable force-sensitive material has to be found, which may be difficult.